Apparatus for feeding a multifilament continuous strand



March 11, 1958 R G, RUSSELL 2,826,293

APPARATUS FOR FEEDING A MULTI-FILAMENT cquwmuous STRAND Filed Nov. 15,1954 Flfilj z-sn ets-shee't 1 IN V EN TOR.

2f Robe/7 G. Russe/l /7 TTORNEYS March 11, 1958 R. e. RUSSELL APPARATUSFOR FEEDING A MULTI-FILAMENT CONTINUOUS STRAND Filed Nov. 15, 1954 2Sheets-Sheet 2 INVENTOR. Robe/v 6. Aussefl ATTORNEYS APPARATUS FORFEEDING A MULTI- FILAMENT CONTINUOUS STRAND Robert G. Russeli,Granville, Ohio, assignor to Owens Corning Fiberglas Corporation, acorporation of Delaware Application November 15, 1954, Serial No.468,861

8 Claims. (Cl. 203-220) This invention relates to apparatus for linearlyfeeding a multi-filament continuous strand, for example, a strandcomprising, say, 200 fine, continuous glass fibers, and thus it relatesto apparatus which may advantageously be used for forming such a strandand for delivering it at a high linear rate to a point of subsequentuse. While the apparatus of the invention has utility for the feeding ofany continuous strand or strand-like material, it willbe illustrated inconnection with the attenuation of fine glass fibers from streams ofmolten glass, their association to form a multi-filament strand and thelinear feeding of such a strand.

Continuous multi-filament glass fiber strands are known in the art astextile strands. Conventionally they are formed by flowing minutestreams of glass through a multiplicity of stream forming orifices,mechanically grasping the ends of the streams as they cool to formfibers and pulling them for attenuating the streams into fine fibers bywinding them at high speed on a spool or rotary package.

Many disadvantages result from this type of operation of which thesignificant ones may be listed as: increasing compression on the packageresulting from the build-up of the strand accumulated thereon,increasing tension on the strand, increasing linear speed of movementdue to increase in radius of the spool, the fact that for subsequent useof the strand it must be unwound from the package on which it isaccumulated, the likelihood of sections of the strand clinging toadjacent sections on the spool, the diificulty of preventing theaccumulated buildup of pressure on the spool from crushing the packageof strands inwardly.

It has been suggested that the difficulties inherent in spool windingand attenuating might be overcome by pulling the associated group offibers linearly between the tes Patent 2,826,293 Patented Mar. 11, 1958forming orifices, etc., could easily be made so that continuous fibersof controlled diameter could be produced at almost any speed.

peripheries of co-acting pulling wheels. Some types of co-acting pullingwheels mounted upon spaced'parallel axes with their peripheries engagingwith opposite sides of the strand and with each other around the strandhave been successful for linear pulling speeds in the order of 10,000feet per minute. In order that such a pulling wheel apparatus be not toobulky, the size of the wheels involved has been kept as small asfeasibly possible and thus their speeds of rotation have beenexcessively high. Because most such wheels are provided with'tires orrims of resilient material the centrifugal forces created by these highspeeds of rotation form a definite limit upon the speed with which anysuch wheels "can be rotated. When the speed of rotation becomestoojhigh, centrifugal force throws particles and pieces o'f'the tires orrims off the wheels, destroying them.

It would be desirable if even "higher speeds of attenuation and feedingcould 'beachieved. 'If speeds, "say, twice as fast, in the order of20,000 .feet per minute, could be achieved without destructive forcesbeing created in the attenuating instrumentalities, appropriatemodifications 'in the constituents of the glass, the size of'stream Itis, therefore, the principal object of this invention to provide pullingwheel apparatus capable of achieving extremely high peripheral speedsand wherein the destructive effects of centrifugal force are controlledby the structure of the pulling wheel instrumentality itself.

The apparatus of the invention is an embodiment of the concept that if arotary structure fabricated, say, from metal and capable of resistingenormous centrifugal forces were constructed in such a manner that themetal could be located exteriorly of the strand contacting surface, thestrength of the metal could be relied upo to prevent the rubber or otherresilient material of the tread from being destroyed by centrifugalforce. Apparatus embodying the invention comprises pulling wheelsarranged not upon spaced, parallel axes with their peripheriescontacting each other approximately in the plane of the axes but,rather, a rotary pulling wheel having an annular flange, the innersurface of which serves as the strand contacting surface and an idlerwheel appropriately mounted with its periphery in contact with theannular strand contacting surface to hold the strand outwardly againstthe strand contacting surface, at least while the pullinginstrumentalities are rotating at slower speeds, for example, when themechanism is starting.

A more complete understanding of the invention and of apparatusembodying it will be realized from the specification which follows andfrom the drawings, in which:

Fig. l is a fragmentary view in front elevation of strand feedingapparatus embodying the invention and shown in its employment for theattenuation and feeding of a multifilament glass fiber strand.

Fig. 2 is a fragmentary side view in elevation of the apparatusillustrated in Fig. 1.

Fig. 3 is a fragmentary View in elevation on a considerably enlargedscale, of portions of the apparatus embodying the invention.

Fig. 4 is a vertical sectional view on an enlarged scale taken along theline 44 of Fig. 1.

Fig. 5 is a fragmentary vertical sectional view taken along the line 55of Fig. 1.

Fig. 6 is a diagrammatic view in vertical section illustrating anotherembodiment ofthe invention.

Fig. 7 is a fragmentary vertical sectional view on an enlarged scale andillustrating a modification of portions of the embodiment of theinvention illustrated in Figs. 1-5.

Fig. 8 is a fragmentary vertical sectional view taken substantially onthe line 88 of Fig. 7.

A continuous glass fiber strand 10 is formed by the association of a.plurality of individual glass fibers 11 which are attenuated fromstreams of glass emitted by stream forming orifices in a bushing ormolten glass container 12. The individual fibers 11 are associatedtogether into the strand 10 by a gathering wheel 13, being grouped inparallelism thereby. Although not illustrated in the drawings, coatingand sizing materials are conventionally added to the fibers at the timeof association into a strand, for example, by dripping them onto thewheel 1'3.

The linear force for attenuating and feeding the strand 1'0 is providedby a high speed rotary pulling wheel generally indicated at 14. Thepulling wheel 14 is mounted upon a shaft 15 and has a generallydisk-like web 16 with an annular flange 17 at its periphery. The flange17 (see particularly Fig. 4) is relatively heavy, being constructed ofmetal which has sufficient strength to withstand the tremendouscentrifugal force created by its high speed rotation without appreciabledeformation. The flange 17 has a return lip 18 forming an annular groovewhich receives a shoulder 19 on a strand contacting tire 20. The tire2t: may have a conical inner surface 21 (shown in slightly exaggeratedform in Figs. 4 and 5).

An idler wheel 22 having a cylindrical periphery is mounted upon aslightly inclined shaft 23 supported, for example, upon a swingingbracket 24, with its periphery in contact with the inner surface 21 ofthe tire 243. While the angle of the axis 23 of the idler wheel 22 isnot critical and while it is shown in exaggerated position in Figs. 4and 5, it will be appreciated that the idler wheel 22 must be mountedupon an axis so tilted with respect to the shaft 15 as to allow thestrand it to enter between the periphery of the idler wheel 22 and thesurface 21 where those surfaces are in contact. T he strand is guidedonto the periphery of the idler wheel 22 and thus into the nip betweenthe inner idler wheel and the surface 21 of the outer pulling wheel 14by a shoe 25 (Figs. 1 and 2). The shoe 25 may be formed of graphite orsimilar smooth, relatively frictionless material over which the strand10 will slide without appreciable resistance and which will not berapidly destroyed by the strand 10 sliding over it.

With the pulling wheel 14 rotating at high speed in the direction of thearrows in Figs. 1 and 3, the idler wheel 22 is also rotated by itsfrictional contact with the surface 21. After an operator has led thestrand it between the peripheries of the wheels 22 and 14, continuedrotation of these wheels exerts tractive force on the strand 10 toattenuate all of the fibers 11 from their molten streams and to feed thestrand l0 outwardly from between the periphery of the wheel 22 and thesurface 21.

Delivery of the strand 10 from between the periphery of the wheel 22 andthe surface 21 may be assisted, or at least started, by an air jetemanating from an air nozzle 26 formed on the end of an air line 27which extends into the space back of the idler wheel 22 and downwardlyto just forward of the nip between the idler wheel 22 and the surface21. The strand 10 is pushed sideways after it leaves the nip by the jetof air from the nozzle 26 and thus it escapes out of the pulling wheel14 and off the surface 21.

After the wheels have been operated for suflicient time to bring them upto the desired operating speed and the strand 10 is flying generallyhorizontally away from the nip between the idler wheel 22 and thesurface 21, the kinetic energy of the portions of the strand which havedeparted from between the nip will become sufficient to pull the strandoutwardly without the use of the jet of air from the nozzle 26. Whenthis condition has been reached the air may be turned off and the strandwill continue to fly generally horizontally away from the two co-actingwheels.

It should be observed that the action of the jet of air from the nozzle26 not only displaces the strand sideways but that it also can bedirected and adjusted to open the strand, separating its lamentssomewhat.

In general the operations of attenuating and feeding the strand throughthe use of apparatus embodying the invention is similar to that whichprevails where pulling wheels mounted upon spaced parallel axes withtheir peripheries in contact around and on opposite sides of the strandare used. Additionally, apparatus of the present invention has the addedadvantage resulting from the fact that the centrifugal force acting uponthe strand itself by reason of its high speed movement through anarcuate path tends to throw the strand out of engagement with the idlerWheel 22, thus obviating the tendency of the strand to wrap around theexterior of the idler wheel 22.

Because of the strong external flange 17 on the pulling wheel 14, thematerial from which the tire 20 is fabricated is placed in compressionrather than tension by centrifugal force and its compression isrestrained by the metal or other strong material forming the flange i7.

There is, therefore, no possibility that the material from which thetire 20 is fabricated will be torn apart by the centrifugal force.Additionally, because the material is in compression rather thantension, its change in dimension under high speed rotation is much less.Resilient material such as natural or synthetic rubber is really notcompressible but merely displaceable and since there is no place towhich the material of the tire 2i) can be displaced, its dimensionsremain virtually stable even when rotating at speeds suiiicient toproduce linear speeds in the order of 20,000 feet per minute or higher.

The present invention may be embodied not only in an annular wheel ofthe type illustrated in Figs. 1-5 but also in an annular wheel formed asa portion of a rotating cylinder such as a cylinder 28 illustrated inFig. 6. In this figure the cylinder 28 has a smooth interior surface andis mounted for rotation in at least a pair of bearings 29 and may bedriven, for example, by a belt 30 engaged in a peripheral pulley 31. Thecylinder 28 has an annular tire 32 mounted upon its interior surfacenear one of its ends, the tire 32 being mounted and shaped similarly tothe tire 20 of Figs. l5. An idler whee. 33 mounted upon its shaft 34 isheld in engagement with the tire 32 in a manner similar to that of theidler wheel 22 in Figs. 1-5.

In operating the apparatus of Fig. 6, an operator threads or leads astrand 35 around the periphery of the idler wheel 33 and into the nipbetween its periphery and the surface of the tire 32. Rotating thecylinder 28 applies tractive force to the strand 35 which attenuates itsfilaments (not shown) and feeds the strand 35 around the inner surfaceof the cylinder 28. As in the case of the embodiment of Figs. 1-5, anair line 36 may be so directed as to emit an air jet at an appropriateplace to initiate movement of the strand 35 axially through the cylinder28. By reason of the high speed of rotation of the cylinder 28 and thejet of air emitted by the pipe 36, the strand 35 assumes a helical formon the interior of the cylinder 28 progressing axially through thecylinder 28.

In Fig. 6 the cylinder 28is illustrated as having a plurality ofinwardlydirected, bent pegs 37 through which the mass of opened fibersof strand 35 are carried. The fibers of strand 35 are separated fromeach other by the action of the jet of air from the pipe 36 and by thespewing or spraying of the strand 35 oif of the tire 32. While theconfiguration of the fibers of the strand 35 shown in Fig. 6 may not beaccurate, it is, in general, the shape and pattern through which theymove when the apparatus is operated at high speed. The mass of fibersgenerally indicated at 38 is led axially away from the cylinder 28 andmay be wound on the exterior of a ball or package 39 which is rotated toapply tractive force to pull away the mass of fibers 38. By reason ofthe high speed of rotation of the cylinder 28 the mass of fibers 38 istwisted gradually being tightened to form what might be termed a rovingor, if the twist is tighter, a cord or rope.

When the operation of the apparatus of Fig. 6 is initiated the operatormay have to begin the flow of the opened fibers axially out of thecylinder 28 by reaching inwardly through its outlet end with a pick orhook to engage the mass of fibers 3S and pull them axially. After theend of the mass of fibers 38 has been engaged with the wind up roll 39,however, the axial force exerted by the wind up roll 39 will keep themass of fibers flowing out of the cylinder 28.

Figs; 7 and 8 illustrate a modification of the periphery of an idlerwheel 40 and the surface of a tire 41 mounted upon a flanged pullingwheel 42. The apparatus fragmentarily shown in Figs. 7 and 8 isidentical with the apparatus of-Figs. 1-5 except that the periphery ofthe idler wheel 40 is scalloped and an inner surface 43 of the tire 41is complementarily scalloped, being closely engaged with the exteriorsurface of the idler wheel 4-0.

By thus shaping the periphery of the idler wheel 40 and the surface 43of the tire 41 the linear length of the surfaces of engagement betweenthe two wheels is increased and the length of engagement of the strandwith the surfaces of the wheel 40 and tire 41 is also lengthened so thata greater tractive force is applied to the strand being attenuated andfed. Such surface configuration may be desirable in order to provide forthe greater traction mentioned and other surface configurations may beemployed with the exterior of the idler wheels 22, 33 or 40 beingcomplementary to and cooperative with the surfaces 21 and 43 of thetires and 41 or the surface of the tire 32.

I claim:

1. Apparatus for feeding a multi-filament strand comprising, incombination, a rotary element having an annular inner surface and anidler wheel in peripheral engagement with said surface and means forguiding said strand circumferentially onto the periphery of said idlerwheel.

2. Apparatus for feeding a multi-filament strand comprising, incombination, a rotary element having an annular inner surface and anidler wheel having its periphery engaged with said surface for rotativemovement therewith and means for guiding said strand circumferentiallyonto the periphery of said idler wheel.

3. Apparatus for feeding a multi-filament strand comprising, incombination, a rotary element having an annular inner surface and anannular resilient tire supported by and located inwardly of, saidannular surface of said element, and an idler wheel mounted for rotationwith its periphery in frictional engagement with the inner surface ofsaid tire, and means for guiding said strand into the bite between theexterior of said idler wheel and the inner surface of said tire.

4. Apparatus according to claim 3 in which said tire has afrusto-conical inner surface and the axis of said idler wheel isinclined to the axis of said rotary element.

5. Apparatus according to claim 3 in which the inner surface of saidtire and the periphery of said idler wheel are complementarily formed.

6. Co-acting rotary pulling wheels for feeding a multifilament strand,one of said wheels having an inner, annular surface of certain diameterand the other of said wheels having an external complementary surface,of smaller diameter, the surfaces of said wheels being frictionallyengaged around and on opposite sides of the strand to be fed.

7. The combination of a rotary strand feeding element having an annular,axially extending rim, a hub and a web joining one axial end of said rimto said hub, an annular resilient tire located interiorly of said rimand a rotary idler wheel mounted on an axis lying in the plane of theaxis of said hub and inclined thereto with the periphery of said wheelin engagement with the inner surface of 'said tire.

8. Apparatus for feeding a multi filament strand comprising, incombination, a rotary hollow cylinder, an an- References Cited in thefile of this patent UNITED STATES PATENTS 2,408,670, McDerrnott Oct. 1,1946 2,670,840 Williams et al Mar. 2, 1954 2,701,936 Drummond Feb. 15,1955

